Epinephrine at a concentration 1.10-5 M in the solution bathing an isolated frog cornea produces a rapid, sustained, and biphasic increase of 2.4 times the original value of the current carried by chloride ions from aqueous to tear side. Aminophylline, cyclic AMP, and dibutyryl cyclic AMP also induced increases in the short circuit current. Epinephrine stimulation doesnot occur or is extremely small in chloride-free solutions. Cl36 fluxes increased in the direction of the transport under the action of aminophylline. The net chloride flux changed from 0.774 to 1.178 µEq.h.-1 cm-2 Cyclic AMP content of the corneas ranged between 7 to 24 pmoles per milligram of protein. Stimulation of the chloride transport by aminophylline produced concommittant dehydration of partially swollen corneas detected as changes in light transmission. It is concluded that epinephrine stimulation of the active transport of the corneal epithelium is mediated by cyclic AMP and that most probably it is related to a physiologic regulation of the corneal epithelium.

Copyright 1972 The Association for Research in Vision and Ophthalmology, Inc.